Merge tag 'rxrpc-rewrite-20160904-1' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Small fixes

Here's a set of small fix patches:

 (1) Fix some uninitialised variables.

 (2) Set the client call state before making it live by attaching it to the
     conn struct.

 (3) Randomise the epoch and starting client conn ID values, and don't
     change the epoch when the client conn ID rolls round.

 (4) Replace deprecated create_singlethread_workqueue() calls.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

9 files changed, 31 insertions, 38 deletions

diff --git a/fs/afs/callback.c b/fs/afs/callback.c
index 7ef637d7f3a5..1e9d2f84e5b5 100644
--- a/fs/afs/callback.c
+++ b/fs/afs/callback.c
@@ -461,8 +461,8 @@ static void afs_callback_updater(struct work_struct *work)
  */
 int __init afs_callback_update_init(void)
 {
-	afs_callback_update_worker =
-		create_singlethread_workqueue("kafs_callbackd");
+	afs_callback_update_worker = alloc_ordered_workqueue("kafs_callbackd",
+							     WQ_MEM_RECLAIM);
 	return afs_callback_update_worker ? 0 : -ENOMEM;
 }
 
diff --git a/fs/afs/flock.c b/fs/afs/flock.c
index d91a9c9cfbd0..3191dff2c156 100644
--- a/fs/afs/flock.c
+++ b/fs/afs/flock.c
@@ -36,8 +36,8 @@ static int afs_init_lock_manager(void)
 	if (!afs_lock_manager) {
 		mutex_lock(&afs_lock_manager_mutex);
 		if (!afs_lock_manager) {
-			afs_lock_manager =
-				create_singlethread_workqueue("kafs_lockd");
+			afs_lock_manager = alloc_workqueue("kafs_lockd",
+							   WQ_MEM_RECLAIM, 0);
 			if (!afs_lock_manager)
 				ret = -ENOMEM;
 		}
diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 244896baf241..37608be52abd 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -76,7 +76,7 @@ int afs_open_socket(void)
 	_enter("");
 
 	ret = -ENOMEM;
-	afs_async_calls = create_singlethread_workqueue("kafsd");
+	afs_async_calls = alloc_workqueue("kafsd", WQ_MEM_RECLAIM, 0);
 	if (!afs_async_calls)
 		goto error_0;
 
diff --git a/fs/afs/vlocation.c b/fs/afs/vlocation.c
index 52976785a32c..45a86396fd2d 100644
--- a/fs/afs/vlocation.c
+++ b/fs/afs/vlocation.c
@@ -594,8 +594,8 @@ static void afs_vlocation_reaper(struct work_struct *work)
  */
 int __init afs_vlocation_update_init(void)
 {
-	afs_vlocation_update_worker =
-		create_singlethread_workqueue("kafs_vlupdated");
+	afs_vlocation_update_worker = alloc_workqueue("kafs_vlupdated",
+						      WQ_MEM_RECLAIM, 0);
 	return afs_vlocation_update_worker ? 0 : -ENOMEM;
 }
 
diff --git a/include/rxrpc/packet.h b/include/rxrpc/packet.h
index b2017440b765..3c6128e1fdbe 100644
--- a/include/rxrpc/packet.h
+++ b/include/rxrpc/packet.h
@@ -24,6 +24,7 @@ typedef __be32	rxrpc_serial_net_t; /* on-the-wire Rx message serial number */
  */
 struct rxrpc_wire_header {
 	__be32		epoch;		/* client boot timestamp */
+#define RXRPC_RANDOM_EPOCH	0x80000000	/* Random if set, date-based if not */
 
 	__be32		cid;		/* connection and channel ID */
 #define RXRPC_MAXCALLS		4			/* max active calls per conn */
diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index 32d544995dda..b66a9e6f8d04 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -16,6 +16,7 @@
 #include <linux/net.h>
 #include <linux/slab.h>
 #include <linux/skbuff.h>
+#include <linux/random.h>
 #include <linux/poll.h>
 #include <linux/proc_fs.h>
 #include <linux/key-type.h>
@@ -700,7 +701,13 @@ static int __init af_rxrpc_init(void)
 
 	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb));
 
-	rxrpc_epoch = get_seconds();
+	get_random_bytes(&rxrpc_epoch, sizeof(rxrpc_epoch));
+	rxrpc_epoch |= RXRPC_RANDOM_EPOCH;
+	get_random_bytes(&rxrpc_client_conn_ids.cur,
+			 sizeof(rxrpc_client_conn_ids.cur));
+	rxrpc_client_conn_ids.cur &= 0x3fffffff;
+	if (rxrpc_client_conn_ids.cur == 0)
+		rxrpc_client_conn_ids.cur = 1;
 
 	ret = -ENOMEM;
 	rxrpc_call_jar = kmem_cache_create(
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index de72de662044..4754c7fb6242 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -868,7 +868,6 @@ skip_msg_init:
 	/* deal with events of a final nature */
 	if (test_bit(RXRPC_CALL_EV_RCVD_ERROR, &call->events)) {
 		enum rxrpc_skb_mark mark;
-		int error;
 
 		clear_bit(RXRPC_CALL_EV_CONN_ABORT, &call->events);
 		clear_bit(RXRPC_CALL_EV_REJECT_BUSY, &call->events);
@@ -876,10 +875,10 @@ skip_msg_init:
 
 		if (call->completion == RXRPC_CALL_NETWORK_ERROR) {
 			mark = RXRPC_SKB_MARK_NET_ERROR;
-			_debug("post net error %d", error);
+			_debug("post net error %d", call->error);
 		} else {
 			mark = RXRPC_SKB_MARK_LOCAL_ERROR;
-			_debug("post net local error %d", error);
+			_debug("post net local error %d", call->error);
 		}
 
 		if (rxrpc_post_message(call, mark, call->error, true) < 0)
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 516d8ea82f02..65691742199b 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -197,8 +197,6 @@ static int rxrpc_begin_client_call(struct rxrpc_call *call,
 	if (ret < 0)
 		return ret;
 
-	call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
-
 	spin_lock(&call->conn->params.peer->lock);
 	hlist_add_head(&call->error_link, &call->conn->params.peer->error_targets);
 	spin_unlock(&call->conn->params.peer->lock);
@@ -586,7 +584,7 @@ static void rxrpc_dead_call_expired(unsigned long _call)
  */
 static void rxrpc_mark_call_released(struct rxrpc_call *call)
 {
-	bool sched;
+	bool sched = false;
 
 	rxrpc_see_call(call);
 	write_lock(&call->state_lock);
diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c
index 4b213bc0f554..82de1aeaef21 100644
--- a/net/rxrpc/conn_client.c
+++ b/net/rxrpc/conn_client.c
@@ -108,12 +108,12 @@ static DECLARE_DELAYED_WORK(rxrpc_client_conn_reap,
 /*
  * Get a connection ID and epoch for a client connection from the global pool.
  * The connection struct pointer is then recorded in the idr radix tree.  The
- * epoch is changed if this wraps.
+ * epoch doesn't change until the client is rebooted (or, at least, unless the
+ * module is unloaded).
  */
 static int rxrpc_get_client_connection_id(struct rxrpc_connection *conn,
 					  gfp_t gfp)
 {
-	u32 epoch;
 	int id;
 
 	_enter("");
@@ -121,34 +121,18 @@ static int rxrpc_get_client_connection_id(struct rxrpc_connection *conn,
 	idr_preload(gfp);
 	spin_lock(&rxrpc_conn_id_lock);
 
-	epoch = rxrpc_epoch;
-
-	/* We could use idr_alloc_cyclic() here, but we really need to know
-	 * when the thing wraps so that we can advance the epoch.
-	 */
-	if (rxrpc_client_conn_ids.cur == 0)
-		rxrpc_client_conn_ids.cur = 1;
-	id = idr_alloc(&rxrpc_client_conn_ids, conn,
-		       rxrpc_client_conn_ids.cur, 0x40000000, GFP_NOWAIT);
-	if (id < 0) {
-		if (id != -ENOSPC)
-			goto error;
-		id = idr_alloc(&rxrpc_client_conn_ids, conn,
-			       1, 0x40000000, GFP_NOWAIT);
-		if (id < 0)
-			goto error;
-		epoch++;
-		rxrpc_epoch = epoch;
-	}
-	rxrpc_client_conn_ids.cur = id + 1;
+	id = idr_alloc_cyclic(&rxrpc_client_conn_ids, conn,
+			      1, 0x40000000, GFP_NOWAIT);
+	if (id < 0)
+		goto error;
 
 	spin_unlock(&rxrpc_conn_id_lock);
 	idr_preload_end();
 
-	conn->proto.epoch = epoch;
+	conn->proto.epoch = rxrpc_epoch;
 	conn->proto.cid = id << RXRPC_CIDSHIFT;
 	set_bit(RXRPC_CONN_HAS_IDR, &conn->flags);
-	_leave(" [CID %x:%x]", epoch, conn->proto.cid);
+	_leave(" [CID %x]", conn->proto.cid);
 	return 0;
 
 error:
@@ -537,6 +521,10 @@ static void rxrpc_activate_one_channel(struct rxrpc_connection *conn,
 					     struct rxrpc_call, chan_wait_link);
 	u32 call_id = chan->call_counter + 1;
 
+	write_lock_bh(&call->state_lock);
+	call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
+	write_unlock_bh(&call->state_lock);
+
 	rxrpc_see_call(call);
 	list_del_init(&call->chan_wait_link);
 	conn->active_chans |= 1 << channel;